Pipe wrench



July 31, 1934. G RICHARDS 1,968,707

PIPE WRENCH Filed Nov. 11, 1953 m INVENTOR BY f a as/2m,

Y Z QTTORNEY Patented July 31, 1934 UNITED STAES PIPE WRENCH James G. Richards, Detroit, Mich, assignor of one-third to Montie P. Atkins and one-third to Dewey G. White, both of Florence, Ala.

Application November 11, 1933, Serial No. 697,660

1 Claims.

The invention relates to improvements in pipe wrenches of the type including a fixed and a movable jaw pivotally connected by non-parallel links, and the principal object of the invention is 5 to provide means whereby wrenches of this type may be adjusted for various requirements. A further object of the invention is to provide means for normally retaining the jaws in open position with the movable jaw urged forward away from the handle. Other objects will become apparent from a consideration of the accompanying drawing, and the further detailed description setting forth an illustrative embodiment of the invention.

In the drawing,

Fig. 1 is a side elevation of a wrench embodying the invention;

Fig. 2 is a similar view illustrating adjustment of the wrench for various sizes of pipes;

Fig. 3 is a top plan view of the wrench shown in Figs. 1 and 2, and

Fig. 4 is a section on line 44 of Fig. 2.

Referring in detail to the drawing, the reference numeral 10 denotes a suitable handle portion at the end of which is formed a fixed jaw 11. Coacting with the fixed jaw is a movable jaw 12. Angular teeth 13 are provided on the fixed jaw and similar teeth 14 on the movable jaw for the purpose of tightly gripping a pipe or other object. The jaws 11 and 12 are swingingly connected by non-parallel links 15 and 16, the link 15 being preferably of greater length than the link 16. Preferably the pivotal points on the movable jaw are closer together than the pivotal points on the fixed jaw in order to assure a tight gripping action on the pipe P on movement of the handle 10 in the direction of the arrow as indicated in Fig. 1.

The link 15 is preferably U-shaped, the legs of the U being pivoted at 17 to the fixed jaw, which is countersunk as at 18, to permit free movement of the link and to provide a smooth exterior surface. The bend 19 of the U engages in one of a plurality of grooves, serrations or the like 20, formed in the outer surface of the movable jaw in such a manner as to vary the normal distance between jaws. The movable jaw is preferably provided with a reduced rear portion 21 of the same thickness as the portion of the upper jaw to which the legs of the U are pivoted, as clearly indicated in Fig. 4. The rear link 16 is preferably composed of a pair of similar link members 16a and 16b pivoted on opposite sides in countersunk portions 23, 23 of the fixed jaw and pivoted at 24 in corresponding countersunk portions 25,25 of the movable jaw. As shown, the handle 10 is provided with a shoulder 26 in rear of the movable jaw. In order to maintain the jaws normally separated so as to retain the link 15 in position and with the movable jaw urged forward away from the handle, a leaf or other spring 27 is provided.

As shown, the leaf is secured to the jaw 11 by means of a fastener 28, while the other end abuts against a notch 29 in the inner face of the movable jaw.

Operation The jaws, being normally held by means of the spring 27 with the movable jaw urged forward with reference to the handle, may be adjusted to the desired extent by placing the bend of the U link 15 in the proper groove 20, as indicated in Fig. 2. The jaws are then engaged with the pipe P with the movable jaw initially in the rearward position. Downward movement of the handle 10, as indicated in Fig. 1, causes the jaws 11 and 12 to tightly grip the pipe with an increasingly firm hold, as indicated in dotted lines in this figure. Owing to the mounting of the links as herein described, free movement is assured and no protruding portions of the link or pivot members will be found in the entire assembly.

When the jaws are inoperative, i. e. not gripping an article, the effect of the spring 27 is to urge the movable jaw both outwardly from the fixed jaw and forwardly away from the handle. When the handle is lowered to produce a gripping effect, the spring will buckle slightly, thereby in creasing the tension. On raising the handle preparatory to securing a new grip, buckling of the spring is released so that the spring tends to straighten out, thus relieving the tension and producing what may be termed a ratchet effect to shift the jaws into position for another bite.

The invention has been described in detail for the purpose of illustration, but it will be understood that variations in detail may be resorted to without departing from the spirit of the invention.

What I claim is:

A self-tightening wrench comprising a jaw carrying a handle, a movable jaw, a series of notches on the outer edge of one jaw, a U-shaped link embracing said jaw and pivoted to the other, a plate spring secured to one jaw, its opposite extremity extending into a notch in the other, and a shorter link pivoted to the jaws in rear of the first-named link, the pivots on the handled jaw being farther apart than those on the other, teeth on the handled jaw inclined toward the handle, and oppositely disposed teeth on the movable jaw. 7

JAMES G. RICHARDS. 

